--- /dev/null
+/**
+ * @fileoverview Rule to enforce line breaks between arguments of a function call
+ * @author Alexey Gonchar <https://github.com/finico>
+ */
+
+"use strict";
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+module.exports = {
+ meta: {
+ type: "layout",
+
+ docs: {
+ description: "enforce line breaks between arguments of a function call",
+ category: "Stylistic Issues",
+ recommended: false,
+ url: "https://eslint.org/docs/rules/function-call-argument-newline"
+ },
+
+ fixable: "whitespace",
+
+ schema: [
+ {
+ enum: ["always", "never", "consistent"]
+ }
+ ],
+
+ messages: {
+ unexpectedLineBreak: "There should be no line break here.",
+ missingLineBreak: "There should be a line break after this argument."
+ }
+ },
+
+ create(context) {
+ const sourceCode = context.getSourceCode();
+
+ const checkers = {
+ unexpected: {
+ messageId: "unexpectedLineBreak",
+ check: (prevToken, currentToken) => prevToken.loc.end.line !== currentToken.loc.start.line,
+ createFix: (token, tokenBefore) => fixer =>
+ fixer.replaceTextRange([tokenBefore.range[1], token.range[0]], " ")
+ },
+ missing: {
+ messageId: "missingLineBreak",
+ check: (prevToken, currentToken) => prevToken.loc.end.line === currentToken.loc.start.line,
+ createFix: (token, tokenBefore) => fixer =>
+ fixer.replaceTextRange([tokenBefore.range[1], token.range[0]], "\n")
+ }
+ };
+
+ /**
+ * Check all arguments for line breaks in the CallExpression
+ * @param {CallExpression} node node to evaluate
+ * @param {{ messageId: string, check: Function }} checker selected checker
+ * @returns {void}
+ * @private
+ */
+ function checkArguments(node, checker) {
+ for (let i = 1; i < node.arguments.length; i++) {
+ const prevArgToken = sourceCode.getLastToken(node.arguments[i - 1]);
+ const currentArgToken = sourceCode.getFirstToken(node.arguments[i]);
+
+ if (checker.check(prevArgToken, currentArgToken)) {
+ const tokenBefore = sourceCode.getTokenBefore(
+ currentArgToken,
+ { includeComments: true }
+ );
+
+ const hasLineCommentBefore = tokenBefore.type === "Line";
+
+ context.report({
+ node,
+ loc: {
+ start: tokenBefore.loc.end,
+ end: currentArgToken.loc.start
+ },
+ messageId: checker.messageId,
+ fix: hasLineCommentBefore ? null : checker.createFix(currentArgToken, tokenBefore)
+ });
+ }
+ }
+ }
+
+ /**
+ * Check if open space is present in a function name
+ * @param {CallExpression} node node to evaluate
+ * @returns {void}
+ * @private
+ */
+ function check(node) {
+ if (node.arguments.length < 2) {
+ return;
+ }
+
+ const option = context.options[0] || "always";
+
+ if (option === "never") {
+ checkArguments(node, checkers.unexpected);
+ } else if (option === "always") {
+ checkArguments(node, checkers.missing);
+ } else if (option === "consistent") {
+ const firstArgToken = sourceCode.getLastToken(node.arguments[0]);
+ const secondArgToken = sourceCode.getFirstToken(node.arguments[1]);
+
+ if (firstArgToken.loc.end.line === secondArgToken.loc.start.line) {
+ checkArguments(node, checkers.unexpected);
+ } else {
+ checkArguments(node, checkers.missing);
+ }
+ }
+ }
+
+ return {
+ CallExpression: check,
+ NewExpression: check
+ };
+ }
+};